Furnace and A/C System Components

Furnace. The furnace contains the blower fan that drives air through the vents. If your air conditioner is on the air will be cold. If the heater is on the air will be hot. The same fan drives all the air through the vents. The furnace also contains the burners, the heat exchanger and many controls and relays that make the equipment work. Your filter is also located near the blower fan. There are many different applications for the filter, but your fan will always draw air through the filter, eliminating dirt and dust in the air.

Coil. The evaporator coil (sometimes called the A-coil because of it's shape) is located in the furnace. When your air conditioner is running, the blower fan blows through this coil and produces cold air from the vents.

Condensing unit. The condensing unit sets outside. The compressor sets in the middle of the unit. It is in the compressor that the compression of freon from a liquid to a gas takes place.
The compressor is surrounded by a condensing coil, the condensing coil helps with the transfer of heat to prevent the compressor from overheating. This coil consists of numerous aluminum fins. These fins need to be kept clean and straight. Bent fins interfere with the transfer of heat. The outside of the unit is covered by a protective case that allows air circulation around the unit. The condenser fan sets on top of the unit and also helps with the transfer from heat generated by the compressor.

Refrigerant lines. The refrigerant lines are the copper lines that run from the outside condensing unit to the coil at the furnace. The freon enters the coil as a gas and as it runs through the system is changed to a liquid. This liquid is pumped back out to the condensing unit where the compressor changes the liquid back to a gas to be run through the system again. This is a sealed system. If you are loosing refrigerant from your system you have a leak.

Thermostat. The thermostat is hooked up to both the heating and cooling system. You can control the blower fan, the furnace and the air conditioner from the thermostat.